An electronic device can be affected by noise and interference from a variety of sources. One source of noise and interference is a varying or alternating magnetic field that can induce undesirable eddy currents in the electronic device. In one example, a varying magnetic field is used to communicate data signals and/or power over an electromagnetic radio frequency (RF) link between electronic devices or components. In this example, the varying magnetic fields can induce eddy currents that adversely affect signal quality and power efficiency of the RF link.
Some hearing prostheses include separate electronic components that are configured to communicate with each other over an electromagnetic RF link. In this example, the RF link allows data communication and/or power transfer between the components. In one example, a hearing prosthesis includes a first component that is external to the person and a second component that is at least partially implanted in the person. In this example, the first component detects sound, encodes the detected sound as acoustic signals, and transmits the acoustic signals to the second component over an electromagnetic RF link between the first and second components. More particularly, the first component generates a varying magnetic field that represents the acoustic signals. The second component receives the varying magnetic field and extracts the acoustic signals. Further, the second component applies the acoustic signals as output signals to the person's hearing system so that the person can perceive the output signals as sound. The output signals applied to the person's hearing system can include, for example, audible signals, vibrations, and/or electrical signals. As discussed generally above, the varying magnetic field generated by the first component can be a source of noise and interference in the first and second components. Generally, it is desirable to design electronic devices in order to reduce undesirable effects of noise and interference and to improve power efficiency.